There was never a plan to ban private-run 2017 WRC cars. FIA's plan was to restrict the drivers who are allowed to drive those cars. Tänak, Prokop, Solberg and even Bertelli are actually good drivers, so no problem for them to get the cars. FIA just doesn't want people like Al-Qassimi(s), Al-Rajhi, and Eurolamp Mini drivers to have them. Though it's not sure whether there will be enough 2017s for privateers in less than six months.